I tried to calculate the possibility of this story.

I found is that the time between the explosion of the rocket and the explosion at the hospital was around 7 seconds. Assuming really ideal cases (namely little air resistance), it would have to be 750 feet in the air.

This seemed really small to me, but I decided to check the feasibility of it anyway. I have no sense of scale in the video, so I figured my best way would be to use projectile motion. Chances were this rocket would be the more common rocket they use, the Qassam.

Rockets are basically projectiles, the same as artillery, so you can use projectile motion to get an idea of it's position. The US military estimates it has a maximum range of about a mile and a half, presumably when fired at 45 degrees. Based off the video, it had already traveled for 14 seconds before exploding.

Using this information, I calculated that the rocket failed at a height of 800 feet, which was really close to the 750 feet I estimated, which seemed to reinforce the Israeli claim about it being a rocket in my opinion.

(this is somewhat reinforced by the fact that the rocket seems to penetrate a cloud layer right before it fails). Assuming these are stratus clouds, they form somewhere around 1000 to 5000 feet, so it's still within the lower range of possibilities.

Seeing that the rocket was fired out of Israel invalidates their claim, I think. Another, is that in some videos you can see the rocket turning, suggesting it was a more advanced weapon. This is not the behavior I'd expect from the Qassam, as it's little more than a hobby rocket. When such a rocket tumbles, it does so chaotically since it has no way to adjust it's flight path (again, it's just an artillery shell with fins). The only possible explanation is that the air density greatly changed, bending it's path the same way rays of light bends when moving from air into water. And all of my math is assuming that it really is Qassam rocket, which seems especially unlikely given the amount of damage. It entered into a cloud layer, so that's a possible explanation.

Another issue I have with their claim is the sound the rocket made when it hit the hospital. It sounded like it was moving at a high speed. Where as, with a rocket mishap at the apex of it's flight wouldn't make such a loud noise as it fell back to Earth.

RT: https://bae.st/objects/f2cd8899-9282-4980-a567-7fc3e9490444